After mining for about a week at a decent speed, I'm starting to seriously doubt I'll ever make ROI. The difficulty just keeps rising...even without the new generation miners. That 3 billion difficulty mark is almost assured by the end of February. Even 2 TH/s rigs are going to be challenged. The whole concept of mining is very tempting, but unless you get your miner for free, or very very cheap...it'll never pay off. The market moves far too quickly to keep up.